Isopropyl alcohol

R. officinalis and L. dentata were collected from Monterrey, N. L., Mexico. The specimens were identified in the Herbarium of the School of Biological Sciences, Universidad Autónoma de Nuevo Leon, Mexico. Dichloromethane (Baker, USA), methanol (Tedia, USA), acetone (CTR Scientific, USA), and isopropyl alcohol (Chromadex, USA) were of HPLC grade. Purified water was from a Milli-Q water-purification system (Veolia, USA). 1,8-cineol (>98%), β-pinene (98.5%), camphor (>95%), 4-allylanisole (98%), and linalool (>95%) were of GC grade (Aldrich, USA). The standard solution was n-alkanes (C8-C24, Sigma-Aldrich, USA). Eudragit EPO, an NC-formed polymer, was obtained from Evonik Industries, Germany.

Lippia graveolens was collected from Cuatro Ciénegas, Coahuila de Zaragoza (26°59′ N 102°03′59″ OE), México. The specimens were identified in the Herbarium of the School of Biological Sciences, Universidad Autónoma de Nuevo León, México. Methanol, acetone (Tedia, Fairfield, OH, USA), and isopropyl alcohol (Chromadex, Los Angeles, CA, USA) were of HPLC grade. Purified water was from a Milli-Q water-purification system (Veolia, Boston, MA, USA). The standard solution n-alkanes (C₈–C₂₀, C₂₂, and C₂₄), myrcene (≥99.5%), p-cymene (≥97%), carvacrol (≥98%), anethole (99%) GC grade, and sodium alginate were purchased from Sigma-Aldrich, St. Louis, MO, USA. Eudragit L100-55 polymer (1:1 methacrylic acid: ethyl acrylate) was purchased from Evonik Industries, Essen, Germany.